1. Field of the Invention
The present invention relates to a vacuum pump apparatus having an improved sealing structure, and in particular to an improved vacuum pump apparatus which is capable of implementing a simple structure without a formation of an O-ring groove for engaging an O-ring therein, a lower fabrication cost, and a stable sealing function and decreasing a maintenance cost.
2. Description of the Background Art
As shown in FIG. 5, a conventional vacuum pump apparatus includes cylinders 104 and 105 for sucking a gas from a vacuum apparatus connected with a pump suction port 102 based on the rotation of rotors 100 and 101, compressing the sucked gas and discharging the gas through a discharging port 103. In the conventional vacuum pump apparatus, the cylinders 104 and 105, a front cover member 106, and a pump cover 107 are assembled.
In addition, an oil pump 111 is installed for implementing a control operation of a reverse flow prevention valve 108 and a lubricating, sealing and cooling operation of each component of the pump apparatus 110. The oil from the oil pump 111 is supplied to each portion of the apparatus including the cylinders 104 and 105 through oil flow paths 112, 113, 114, 115 and 116.
Since the interior of the pump apparatus 110, namely, the cylinders 104 and 105 has a high temperature, an O-ring groove is formed in assembled boundary surfaces 117, 118 and 119 of the member 104, 105, 106 and 107, respectively, for sealing the same, and an O-ring 120 is engaged to each O-ring groove so that a gas(air) is not flown from the outside of the pump apparatus 110.
However, in the conventional sealing structure, since the O-ring grooves are formed in the assembled boundary surfaces 117, 118 and 119 of the members 104, 105, 106 and 107, a fabrication cost is increased. Since the O-ring 120 is directly contacted with an oil and gas, as the time is passed, the O-ring 120 is corroded for thereby decreasing a sealing performance of the O-ring 120. In addition, since the O-ring 120 is frequently changed, the pump apparatus 110 is frequently disassembled for thereby increasing a maintenance cost.
Accordingly, it is an object of the present invention to provide a vacuum pump apparatus which is capable of implementing a simple structure without a formation of an O-ring groove for engaging an O-ring therein, a lower fabrication cost and a stable sealing function and decreasing a maintenance cost.
To achieve the above object, there is provided a vacuum pump apparatus in which a circular oil seal space is formed in assembling boundary surfaces of a cylinder, an oil pump housing and an oil pump cover which are sequentially assembled, wherein said oil seal space is communicated with an oil flow path through which an oil is supplied from the oil pump to each operating portion of a pump apparatus for thereby implementing a sealing effect based on an oil pressure in the vacuum pump which includes a cylinder for sucking and compressing a gas from a vacuum facility by a rotor, an oil pump housing which protects an oil pump installed at an end portion of a rotor shaft and an oil pump cover.